This invention relates to apparatus for forming blocks such as building blocks.
Various different machines for forming building blocks are known. Some of these machines use a hydraulic ram to compress a soil/cement mixture in a compression chamber to form a building block. Other machines use non-hydraulic mechanisms to compress the soil/cement mixture.
Although the hydraulic machines are usually relatively quick in operation, they are relatively complicated and expensive. On the other hand, although mechanical machines may be relatively inexpensive and simple to manufacture, their throughput is substantially less.
It is an object of the invention to provide an alternative apparatus for forming building blocks.
According to the invention apparatus for forming blocks comprises:
an upright compression chamber having first and second opposed ends, with a common inlet and outlet at the first, upper and thereof;
a ram movable between an extended position in which is extends into the compression chamber towards the first end thereof, and a retracted position towards the second end thereof; and
a gate slidable transversely relative to the axis of travel of the ram to close off the common inlet and outlet of the compression chamber, so that the compression chamber can be filled with particulate material to be compressed and a block formed therefrom can be ejected via the common inlet and outlet.
The ram may be arranged to be driven by a first hydraulic cylinder disposed below the second end of the compression chamber.
The gate is preferably arranged to be driven by a second hydraulic cylinder disposed adjacent to the first end of the compression chamber.
The gate may comprise a plate having an inner surface defining an end wall of the compression chamber and being slidable in grooves or channels at the first end of the compression chamber.
Preferably, the ram is arranged to apply force to the particulate material in the compression chamber while the gate is opened after compression of the particulate material.
The inner surface of the plate is preferably formed with inclined shoulders at opposed edges thereof, so that sliding movement of the gate forms opposed bevelled edges on the adjacent end surface of a building block in the compression chamber.
The outer surface of the ram preferably has inclined shoulders at opposed edges thereof, so that if forms opposed bevelled edges on the adjacent and surface of a building block in the compression chamber.
The compression chamber may be supported on a free-standing frame.
The frame may include at least one lifting formation engageable by conventional lifting means such as a hydraulic boom.
Wheels may be fitted to the frame to allow towing of the apparatus.
The frame may support a hydraulic pump which is arranged to be driven from the power take-off of a tractor or another power source.